fromJson static method

QueryPredicate? fromJson(dynamic value)

Returns a new QueryPredicate instance and imports its values from value if it's a Map, null otherwise.

Implementation

// ignore: prefer_constructors_over_static_methods
static QueryPredicate? fromJson(dynamic value) {
  if (value is Map) {
    final json = value.cast<String, dynamic>();

    // Ensure that the map contains the required keys.
    // Note 1: the values aren't checked for validity beyond being non-null.
    // Note 2: this code is stripped in release mode!
    assert(() {
      assert(json.containsKey(r'key'), 'Required key "QueryPredicate[key]" is missing from JSON.');
      assert(json[r'key'] != null, 'Required key "QueryPredicate[key]" has a null value in JSON.');
      assert(json.containsKey(r'value'), 'Required key "QueryPredicate[value]" is missing from JSON.');
      assert(json[r'value'] != null, 'Required key "QueryPredicate[value]" has a null value in JSON.');
      assert(json.containsKey(r'operator'), 'Required key "QueryPredicate[operator]" is missing from JSON.');
      assert(json[r'operator'] != null, 'Required key "QueryPredicate[operator]" has a null value in JSON.');
      return true;
    }());

    return QueryPredicate(
      key: mapValueOfType<String>(json, r'key')!,
      value: QueryPredicateValue.fromJson(json[r'value'])!,
      operator_: QueryPredicateOperator_Enum.fromJson(json[r'operator'])!,
    );
  }
  return null;
}